Jennifer Rubin, Washington Post: Commentators such as Jack Shafer argue the media should ignore President-elect Donald Trump's outlandish tweets -- because they are outlandish and because they distract us from things Trump wants us to ignore. ... [W]e would argue that there is no more important story than the continuous stream of evidence of the president-elect's irrationality and instability. Hillary Clinton certainly thought that was relevant to the campaign (it was); the mental and intellectual status of the man we elected should be of even greater concern. ... How are we to trust the decision-making of a president so easily waylaid by nonsense?

Does Trump's lack of attention span and refusal to read make him susceptible to conspiracy theories? Can he continue his willful indifference to reality and still govern? Do his personal grievances interfere with his ability to function as president? Who, if anyone, can reason with a man this irrational? ...

In sum, no one can assess at this stage whether Trump tweets strategically or compulsively, whether he means what he tweets or simply tweets to blow off steam, and whether he understands the importance of a president's words. Perhaps clarity will come with time. For now, however, his utterances on Twitter and elsewhere give critical insight into the mind-set of the least prepared man ever to win the presidency.